Enhanced light absorption and through-thickness heat conduction of vertically aligned transferable carbon nanotube/silicone rubber composite films

Abstract

Easily manageable flexible films of multi-walled carbon nanotubes (MWCNT) were prepared and characterized. For the preparation of the MWCNTs pulsed laser-induced dewetting (PLiD) of stainless steel surfaces is employed to generate freely designable arrays of catalytic nanoparticles (NP), which facilitate the MWCNT growth in a chemical vapor deposition (CVD) process. The density of the NP fields, and thus the areal density of the CNTs grown, can be controlled through the used laser parameters. As prepared CNT-arrays were soaked with silicone and cross-linked to form a flexible detachable film that may be reattached onto any other surface. The silicone matrix increases reflection only minimally by about 2%. The vertically aligned CNT (VACNT) arrays were undisturbed during capillary filling of silicone. The anisotropic heat transfer properties of the VACNTs are preserved. Such films are excellent light-absorbers and e.g. may enhance the effectiveness of solar panels or transfer heat from microprocessors to a cooling system.